Log, Jan 18, 2008

52 people. The sky was in a very unusual condition last night - it was actually transparent!! We could actually see those tiny little lights that we used to call stars. Oh yeah, the Moon was out in a fat gibbous phase, but so were Mars, and M35, and Praesepe, and the Great Nebula in Orion as well as the Great Galaxy in Andromeda. And late in the evening, Saturn made its first official appearance of the year at FDO. We had to rush people through the Moon viewing and Mars viewing because both of them very almost overhead at 6:30. Now for most telescopes, overhead means ideal viewing but we have two problems with this. First of all, the shutter in its normal configuration blocks the Zenith. This can be altered but the second problem is much greater - the eyepiece is constrained by the yoke which holds the scope's main barrel. It is possible to remove lots of parts of the telescope and rebalance the whole affair but the eyepiece remains almost impossible to reach and the time to disassemble and reassemble everything would take many hours. So we don't try for the Zenith.

We spent a good deal of time looking at the Great Nebula in Orion. Nominally this is M42 but it merges with the nearby M43. Sky and Telescope magazine has a large article on the Sword (actually the sword's scabbard) in the February 2008 issue. Actually the entire sword is NOT stars but deep space objects. The hilt of the sword is an open cluster of stars (NGC1981, relatively faint). Just below it is NGC1977 (a diffuse nebula illuminated by two fourth magnitude stars), just below them is the Great Nebula itself (M43/NGC1983 and M42/NGC1976). It contains the famous Trapezium of newly formed stars [which I call "the baby stars" in my nightly babble]. A trapezoid is a four sided figure - so you might suspect that the Trapezium is 4 stars - and so it is if you count just the bright stars in the group [officially Theta Orionis 1 A, B, C and D]. However there are at least three other stars inside the trapezoid [E, F and G]. I actually caught glimpses of E and F last night but I didn't try to have the assembled masses find them. Finally at the point of the sword you'll find the only easily visible star Iota Orionis.

-Les Coleman

Leslie Coleman
Leslie Coleman
Entry Date:
Jan 18, 2008
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Leslie Coleman's Log
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